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This guide was created as an overview of the Linux Operating System, geared toward new users as an exploration tour and getting started guide, with exercises at the end of each chapter.
For more advanced trainees it can be a desktop reference, and a collection of the base knowledge needed to proceed with system and network administration. This book contains many real life examples derived from the author's experience as a Linux system and network administrator, trainer and consultant. They hope these examples will help you to get a better understanding of the Linux system and that you feel encouraged to try out things on your own.

I can see / run the ping command, I can ping my LAN all day no problem. Heck I can even ping the WAN side of my router, but Can't ping anything further out. I have also tried pinging from boxes running Win 98 / Win XP / SuSE PRO / SuSE (standard). So it's not the O.S. doing it.

try typing
echo 0 > /proc/sys/net/ipv4/icmp_echo_ignore_all
not sure if that effects outgoing pings or not.. i dont think it does...

This stops the box itself from replying to pings...
Wouldn't have any effect on forwarded pings..

Quote:

Yeah, Pings is not a PORT, but you need to have ICMP activated with IPTABLES. So I call it a port.

Ping and other protocols are always activated in the kernel, (unless you remove them)..
iptables merely gives you some control over them.. eg writing a rule to block, redirect etc
You would only need to allow them if you had a DROP policy to catch unspecified connections.

The 2 rules m15a4 mentioned have no effect on outgoing pings...
So I would suggest as killer_bunny did, isolate the problem.
Clear the rules and eliminate them as a possible cause...
Also add some -j LOG entries via the command line to watch what is happening...
eg iptables -t nat -I POSTROUTING -j LOG

When listing rules, please use iptables-save to print them on the screen.
iptables -nL only shows 1 table and interpretes the rules quite inaccurately..